Re: [Help-smalltalk] JIT and ContextPart/Exception issue

[Holger Hans Peter Freyther]

On Sat, Feb 01, 2014 at 06:28:07PM +0100, Holger Hans Peter Freyther wrote:
> On Mon, Jan 20, 2014 at 02:44:38PM +0100, Holger Hans Peter Freyther wrote:
> 
> Hi Paolo,

Hi again,

so maybe there are two bugs. The JIT should not assume a "dense" bytecode
and actually know where/if there is a next bytecode and somehow I think
there should not be a gap? The below is the easiest re-producer of the
issue.


Object subclass: Foo [
        bytecodeIndex [
        ]

        dispatchTo [
        "Disassemble the bytecodes and tell anObject about them in the form
         of message sends.  param is given as an argument to every message
         send."

        <category: 'decoding bytecodes'>
        | lastOfs anObject param i byte arg |
                anObject := self.
                "Remove the send to have the issue go away"
                anObject bytecodeIndex.
                self
                    dispatchByte: byte
                    with: arg
                    at: i
                    to: anObject
                    with: param
    ]
]

Eval [
"        ((CompiledMethod lookupSelector: #dispatchTo:with:) literalAt: 3) 
inspect.
        (CompiledMethod lookupSelector: #dispatchTo:with:) methodSourceString 
printNl.
        (Foo >> #dispatchTo) inspect."

        Foo new dispatchTo
]


An instance of CompiledMethod
  header: 12416
  Header Flags: 
    flags: 0
    primitive index: 0
    number of arguments: 0
    number of temporaries: 6
    number of literals: 2
    needed stack slots: 16
  descriptor: a MethodInfo
  literals: [
    [1] #bytecodeIndex
    [2] #dispatchByte:with:at:to:with:
  ]
  byte codes: [
Code...?
    [1] source code line number 5
    [3] source code line number 8
        push self
    [5] store into Temporary[1]
        source code line number 9
    [7] send 0 args message #bytecodeIndex
    [9] source code line number 10
        pop stack top
        push self
   [11] source code line number 11
        push Temporary[4]
   [13] source code line number 12
   [15] push Temporary[5]
   [17] source code line number 13
        push Temporary[3]
   [19] source code line number 14
        push Temporary[1]
   [21] source code line number 15
        push Temporary[2]
   [23] send 5 args message #dispatchByte:with:at:to:with:
   [27] push self
        return stack top
  ]


note [23] and [27]. I am not sure if there is actually anything
between these two?